Process for producing particulate iron-antimony containing oxide composition having high compressive strength

Abstract

There is provided a process for producing a particulate iron-antimony containing oxide composition having high compressive strength, comprising the steps of: providing an aqueous slurry containing iron ions, nitrate ions and antimony trioxide; adjusting the slurry to a pH value in the range of 0.5 to 3 as measured at 40 DEG C.; heating the slurry; spray-drying the heated slurry; and calcining the resultant particles.

What is claimed is: 
     
       1. A process for producing a particulate iron-antimony containing oxide composition having high compressive strength, which comprises providing an aqueous slurry consisting essentially of water, iron ions, nitrate ions and antimony trioxide; adjusting the slurry to a pH value in the range of 0.5 to 3 as measured at 40° C.; heating the slurry; spray-drying the heated slurry; and calcining the resultant particles. 
     
     
       2. The process according to claim 1, wherein the slurry is adjusted to a pH value in the range of 0.8 to 2.7 as measured at 40° C. and contains ammonium nitrate. 
     
     
       3. The process according to claim 1, wherein the atomic ratio of iron to antimony in the composition is 5 to 23 atoms of antimony to 10 atoms of iron. 
     
     
       4. The process according to claim 1, wherein the calcination is carried out in a nitrogen atmosphere at a temperature of 400 to 950° C.